Cyclopropane is one of the most reactive functionalities owing to its intrinsic ring strain. Transition-metal catalysis and Lewis acid catalysis have been extensively used in ring openings of cyclopropanes; however, Lewis base-catalyzed activation of cyclopropanes remains largely unexplored. Upon nucleophilic attack with Lewis bases, cyclopropanes undergo ring cleavage in a manner known as homoconjugate addition to form zwitterionic intermediates, which have significant potential for reaction development but have garnered little attention. Here, we present a brief overview of this area, with an emphasis on our recent efforts on Lewis base-catalyzed rearrangement reactions of electron-deficient cyclopropanes using the homoconjugate addition process. 1 Introduction 2 DABCO-Catalyzed Cloke–Wilson Rearrangement of Cyclopropyl Ketones 3 Hydroxylamine-Mediated Tandem Cloke–Wilson/Boulton–­Katritzky Reaction of Cyclopropyl Ketones 4 Phosphine-Catalyzed Rearrangement of Vinylcyclopropyl Ketones To Form Cycloheptenones 5 Phosphine-Catalyzed Rearrangement of Alkylidenecyclopropyl Ketones To Form Polysubstituted Furans and Dienones 6 Conclusion and Outlook

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基于同共轭加成的路易斯碱催化：缺电子环丙烷及其衍生物的重排

由于其固有的环应变，环丙烷是最具反应性的官能团之一。过渡金属催化和路易斯酸催化已广泛用于环丙烷的开环；然而，路易斯碱催化的环丙烷活化在很大程度上仍未得到探索。在与路易斯碱进行亲核攻击时，环丙烷以一种称为同共轭加成的方式发生开环，形成两性离子中间体，其具有显着的反应发展潜力，但很少引起关注。在这里，我们简要概述了该领域，重点介绍了我们最近在使用同共轭加成过程对缺电子环丙烷进行路易斯碱催化重排反应的研究。